10-2 How Should We Manage and Sustain Forests?

• Concept 10-2 We can sustain forests by emphasizing the economic value of their ecological services, removing government subsidies that hasten their destruction, protecting old-growth forests, harvesting trees no faster than they are replenished, and planting trees.

Solution: Sustainable Forestry• Biodiversity researchers and a growing number of

foresters have called for more sustainable forest management• Identify and protect forest areas

________ in biodiversity• Rely more on _____________ and

_____________ cutting• Stop logging in _________________ forests• Reduce _________ building in uncut forest areas• Leave dead or fallen timber for wildlife

_____________ and nutrient _______________

highselective

strip

old-growthroad

habitat cycling

Solution: Sustainable Forestry

• Put tree plantations only on _________________ or degraded land

• ________________ timber grown bysustainable methods

• Include ____________________ services of forests in estimates of

their economic value

deforested

Certify

ecological

Science Focus: Certifying Sustainably Grown Timber

• Collins Pine is a forests products _____________that owns and manages large areas of timberland in California, Oregon and Pennsylvania • Has used selective cutting since the 1940s

• Each year their land is evaluated by a subsection of the _____________ _______________ Council and they are awarded with a _______ logo on their products• Only ______ of the world’s forest area in 82 countries

has been certified according to FSC standards

company

Forest StewardshipFSC

5%

We Can Improve the Management of Forest Fires

• In the U.S., the _____________ _________ educational campaign has saved many lives and prevented countless forest fires• Downside?…the advertising campaign has convinced

much of the public that all forest fires are ________

• We actually need _________________ to prevent the build up of flammable underbrush which may cause crown fires

• To reduce this risk, one strategy is to conduct _________________ fires…setting small, contained surface fires to reduce the buildup of underbrush

Smokey Bear

bad

surface - fires

prescribed

• A second strategy is to allow some fires on public lands to ____________

• A third strategy is to __________ out a forest zone surrounding _____________ or other fire prone buildings

• A fourth strategy is to thin forest areas vulnerable to fire by removing ____________ trees

burn

thinhouses

small

We Can Reduce the Demand for Harvested Trees

• One way to reduce the pressure on forest ecosystems is to improve the efficiency of wood ________• 60% of U.S. wood consumed is wasted• This results from…• Inefficient use of ____________________ materials• Excess __________________• Overuse of _________ mail• Inadequate paper __________________

use

constructionpackagingjunk

recycling

We Can Reduce the Demand for Harvested Trees

• We can reduce our need to harvest trees by making paper from ______________ resources• China uses

_______________• U.S. uses a small amount

of __________ (kuh-NAHF)

• Other possible options…hemp, kudzu vine

kenaf

tree-free

rice straw

kenaf

• So to reduce our demand for harvesting trees, we need to be…• Reducing ________________• Finding ________________• Embracing _________________ use

waste

alternativessustainable

Case Study: Deforestation and the Fuelwood Crisis

• About _______ of the wood we harvest world-wide is used for __________

• Less-developed countries use fuelwood for _______________ and _______________

• Ex: Haiti was once a tropical paradise , but now it is an ecological _______________ because its trees were harvested for fuelwood

halffuel

heating cooking

disaster

Mangrove Forest in Haiti Chopped Down for Fuelwood

Fig. 10-18, p. 232

Case Study: Deforestation and the Fuelwood Crisis

• Possible solutions• Establish small plantations of _______________

fuelwood trees and shrubs• Burn wood more efficiently with better

_____________ (that also produce less pollution)• Solar or wind-generated electricity• Burn garden ______________

fast-growing

stoves

waste

Governments and Individuals Can Act to Reduce Tropical Deforestation

• Help settlers to develop ____________________ sustainable agriculture and forestry in tropical forest

• Government _________________ for forest land

• Debt-for-nature swaps/conservation concessions• Example: Brazil’s dairy farmers receive _____________

assistance as long as they are reforesting and maintaining their land…____________ milk yields and ______________ their incomes

• Plant trees

• Buy certified lumber and wood products

small-scale

protection

technical

tripled doubled

Fig. 10-19, p. 233

Solutions

Sustaining Tropical Forests

Prevention Restoration

Protect the most diverse and endangered areas

Encourage regrowth through secondary succession

Educate settlers about sustainable agriculture and forestry

Subsidize only sustainable forest use

Rehabilitate degraded areasProtect forests through

debt-for-nature swaps and conservation concessions

Certify sustainably grown timber

Concentrate farming and ranching in already-cleared areas

Reduce poverty

Slow population growth

10-3 How Should We Manage and Sustain Grasslands?

• Concept 10-3 We can sustain the productivity of grasslands by controlling the number and distribution of grazing livestock, and by restoring degraded grasslands.

Some Rangelands Are Overgrazed (1)• After forests, grasslands are the ecosystems most

widely used and altered by humans

• Rangelands• ____________________ grasslands in temperate and

tropical climates that provide forage for animals• Grazing = _________________• Browsing = __________________

• Pastures• ____________________ grasslands and fenced

meadows used for grazing livestock

unfenced

grassshrubs

managed

Some Rangelands Are Overgrazed (2)• Important ecological services of grasslands• ____________________ formation• Erosion _____________________• Nutrient _________________• Storage of atmospheric _______ in biomass• Maintenance of biodiversity

• Cattle and sheep currently graze on about _____ of the world’s grasslands…estimated to increase to _______ by 2050.

Soilcontrol

cyclingCO2

42%

70%

Some Rangelands are Overgrazed (3)• Overgrazing of rangelands occurs when too many

animals graze for too long…damaging the ________ of grasses and exceeding the area’s _____________ _______________• Reduces grass cover• Leads to erosion of soil by water and wind• Soil becomes compacted…diminishes capacity to hold

_____________• Enhances invasion of plant species that cattle won’t

eat

rootscarrying

capacity

water

Natural Capital Degradation: Overgrazed and Lightly Grazed Rangeland

Fig. 10-20, p. 234

Case Study: The Malpai Borderlands• Malpai Borderlands• Grasslands located by the ___________________

__________________ border• For more than a century, ranchers there….• Allowed __________________• _________________ fires….allowed trees and shrubs

to replace grasses• Management success story• Since 1993, ranchers, scientists, environmentalists, and

governing agencies began working together to restore the grasslands – conducted periodic _______________ burns

Arizona -New Mexico

overgrazingsuppressed

controlled

Natural Capital Restoration: San Pedro River in Arizona

Fig. 10-21, p. 235

__________________ zoneriparian

We Can Manage Rangelands More Sustainably (1)

• More sustainable management of rangelands…

• _________________ grazing – cattle are confined by portable fencing to one area for a ____________ time and then moved to a new location

• Suppress growth of ________________ species• Herbicides• Mechanical removal• Controlled burning• Controlled short-term ______________________

• Replant barren areas with ___________ grasses and applying fertilizer…more expensive option

Rotationalshort

invasive

trampling

native

Case Study: Grazing and Urban Development the American West

• American southwest population surge since 1980

• Some ranchers have been selling their land to _________________

• To sustain our remaining grasslands, we have been working to __________________ cattle ranches• Land trust groups pay ranchers for conservation

_________________ - deed restrictions that bar future owners from developing the land

• Pressuring local governments to ___________ the land

developers

preserve

easements

zone

Review Questions

• What does an FSC logo indicate?

• Why are surface fires needed?

• What is meant by the term “fuelwood crisis”?

• What methods will help us to sustain grasslands?

It is certified as sustainably made

To remove flammable underbrush & maintain grasslands

½ of our wood is used for fuel by LDCsand they need alternatives

Rotational Grazing Suppress Invasive Species Replant/Fertilize